Saturday, 24 February 2018

Supergranulation on a Blank Sun - 24th february

Todays sun is totally blank of all our usual features; active regions, sunspots and the like.  However look a little closer and this calcium image of our star shows 'Supergranulation', this pattern of convection cells on the Suns surface was discovered by A.B. Hart in the 1950's using doppler techniques to identify the flows of plasma on the photosphere.  Supergranulation has an approximate size of 30000km in diameter with a lifetime of about 24hrs and a surface flow speed of between 300m/s and 500m/s.  This image was taken with the ED60 at f6 with the homebrew CaK filter and the PGR Chameleon 3 camera, this first impressions with the scope at these short wavelengths is very favourable.  

I had planned on quite an observing session today, giving a number of scopes their first airing for the new year, however immediately on setting up the HEQ6 mount was dead and would not fire up; investigation revealed a fried inductor on PCB, likely caused by a short as can be seen in the image below.  Looks like a new board is in order.